Distributed IP gateway based on sharing a MAC address and IP address concurrently between a first network switching device and a second network switching device

1. A method comprising: assigning, by a distributed gateway protocol circuit in a first network switching device, a shared Media Access Control (MAC) address to a shared Internet Protocol (IP) address, the shared MAC address and the shared IP address being configured to enable connected network devices to reach a distributed IP gateway in a network, the distributed IP gateway comprising at least two network switching devices operating concurrently with each other, the concurrent operation based on enabling a combined use of first hop redundancy protocols (FHRP) and multiple data link channels in the at least two network switching devices; claiming, with the distributed gateway protocol circuit in the first network switching device, active control over the distributed IP gateway; and sending, by a layer 2 forwarding circuit in the first network switching device, an instruction via a peer data link to a peer layer 2 forwarding circuit in a second network switching device in response to the distributed gateway protocol circuit in the first network switching device claiming active control of the distributed IP gateway and based on determining the shared MAC address is assigned to a layer 2 virtual large area network (VLAN) group that is configured for multichannel link layer communications, the instruction enabling the second network switching device to operate concurrently with the first network switching device as part of the distributed IP gateway based on concurrent use of the shared MAC address and the shared IP address by the first network switching device and the second network switching device.

2. The method of claim 1 , wherein: the assigning includes binding the shared MAC address and the shared IP address with a group identifier for the distributed IP gateway, and sending the shared MAC address to the layer 2 forwarding circuit; the method further comprises the layer 2 forwarding circuit responding to the shared MAC address from the distributed gateway protocol circuit by creating a layer 2 state table entry to specify the shared MAC address, a corresponding local state of the layer 2 forwarding circuit for the shared MAC address, a corresponding remote state of the peer layer 2 forwarding circuit for the shared MAC address, and a layer 2 forwarding action identifying a corresponding execution state of the layer 2 forwarding circuit for the shared MAC address.

3. The method of claim 2 , wherein the responding includes setting the local state for the shared MAC address to reserve an entry in a layer 2 forwarding table in the first network switching device for MAC address learning, and setting the remote state to specify the second network switching device does not claim active control of the distributed IP gateway.

4. The method of claim 3 , further comprising: in response to the distributed gateway control circuit claiming the active control of the distributed IP gateway, sending a second instruction to the layer 2 forwarding circuit to change the local state for the shared MAC address to an active state; the sending of the instruction by the layer 2 forwarding circuit including: changing the local state for the shared MAC address to the active state in response to the second instruction, and changing the layer 2 forwarding action to specify the execution state for the shared MAC address as executing a prescribed layer 3 gateway operation, the layer 2 forwarding circuit sending the instruction to the peer layer 2 forwarding circuit in response to the local state for the shared MAC address being changed to the active state.

5. The method of claim 4 , further comprising the layer 2 forwarding circuit executing the prescribed layer 3 gateway operation based on causing each network switch port circuit of the first network switching device to forward a received packet, destined for the shared MAC address, to a prescribed layer 3 gateway circuit in the first network switching device.

6. The method of claim 2 , further comprising: the peer layer 2 forwarding circuit implementing the instruction based on creating a peer layer 2 state table entry for the shared MAC address in the second network switching device, the peer layer 2 state table entry specifying the shared MAC address, the corresponding state of the peer layer 2 forwarding circuit as one of forwarding received packets to the first network switching device via the peer data link or forwarding the received packets to a prescribed layer 3 gateway device; the peer layer 2 forwarding circuit selectively setting the corresponding state of the peer layer 2 forwarding circuit based on a determined status of the second network switching device relative to the shared MAC address.

7. The method of claim 6 , further comprising: the second network switching device receiving a packet addressed to the shared MAC address from one of the connected network devices while the first network switching device claims the active control; and the second network switching device executing layer 3 forwarding of the packet to a connected gateway device while the first network switching device claims the active control, based on the peer layer 2 forwarding circuit determining the status of the second network switching device relative to the shared MAC address as having a standby state relative to the distributed IP gateway.

8. The method of claim 7 , further comprising: the second network switching device determining an inability to forward the packet to the connected gateway device, the peer layer 2 forwarding circuit in response updating the corresponding state of the peer layer 2 forwarding circuit as forwarding received packets to the first network switching device via the peer data link.

9. An apparatus comprising: a distributed gateway protocol circuit configured for: assigning a shared Media Access Control (MAC) address to a shared Internet Protocol (IP) address, the shared MAC address and the shared IP address being configured to enable connected network devices to reach a distributed IP gateway in a network, the distributed gateway protocol circuit configured for selectively claiming active control of the distributed IP gateway, the distributed IP gateway comprising at least two network switching devices operating concurrently with each other, the concurrent operation based on enabling a combined use of first hop redundancy protocols (FHRP) and multiple data link channels in the at least two network switching devices, and claiming active control over the distributed IP gateway; one or more network interface circuits having a plurality of network switch port circuits, each network switch port circuit configured for establishing a corresponding data link with one of the connected network devices or a connected network switching device; and a layer 2 forwarding circuit configured for sending an instruction to the connected network switching device via the corresponding data link in response to the distributed gateway protocol circuit in the first network switching device claiming the active control of the distributed IP gateway and based on determining the shared MAC address is assigned to a layer 2 virtual large area network (VLAN) group that is configured for multichannel link layer communications, the instruction enabling the connected network switching device to operate concurrently with the apparatus as part of the distributed IP gateway based on concurrent use of the shared MAC address and the shared IP address by the apparatus and the connected network switching device.

10. The apparatus of claim 9 , further comprising a memory circuit, wherein: the distributed gateway protocol circuit is configured for binding the shared MAC address and the shared IP address with a group identifier for the distributed IP gateway, and sending the shared MAC address to the layer 2 forwarding circuit; the layer 2 forwarding circuit configured for responding to the shared MAC address from the distributed gateway protocol circuit by creating in the memory circuit a layer 2 state table entry to specify the shared MAC address, a corresponding local state of the layer 2 forwarding circuit for the shared MAC address, a corresponding remote state of the peer layer 2 forwarding circuit for the shared MAC address, and a layer 2 forwarding action identifying a corresponding execution state of the layer 2 forwarding circuit for the shared MAC address.

11. The apparatus of claim 10 , wherein the layer 2 forwarding circuit is configured for setting the local state for the shared MAC address to reserve an entry in a layer 2 forwarding table in the memory circuit for MAC address learning, and setting the remote state to specify the connected network switching device does not claim active control of the distributed IP gateway.

12. The apparatus of claim 11 , wherein: the distributed gateway control circuit is configured for claiming the active control of the distributed IP gateway based on a prescribed protocol, and in response sending a second instruction to the layer 2 forwarding circuit to change the local state for the shared MAC address to an active state; the layer 2 forwarding circuit further configured for: changing the local state for the shared MAC address to the active state in response to the second instruction, and changing the layer 2 forwarding action to specify the execution state for the shared MAC address as executing a prescribed layer 3 gateway operation, and sending the instruction to the peer layer 2 forwarding circuit in response to the local state for the shared MAC address being changed to the active state.

13. The apparatus of claim 12 , further comprising a prescribed layer 3 gateway circuit, wherein the layer 2 forwarding circuit executing the prescribed layer 3 gateway operation based on causing each network switch port circuit to forward a received packet, destined for the shared MAC address, to the prescribed layer 3 gateway circuit.

14. An apparatus comprising: means for assigning a shared Media Access Control (MAC) address to a shared Internet Protocol (IP) address, the shared MAC address and the shared IP address being configured to enable connected network devices to reach a distributed IP gateway in a network, the means for assigning configured for selectively claiming active control of the distributed IP gateway, the distributed IP gateway comprising at least two network switching devices operating concurrently with each other, the concurrent operation based on enabling a combined use of first hop redundancy protocols (FHRP) and multiple data link channels in the at least two network switching devices; means for claiming active control over the distributed IP gateway; one or more network interface circuits having a plurality of network ports, each network port configured for establishing a corresponding data link with one of the connected network devices or a connected network switching device; and means for sending an instruction to the connected network switching device via the corresponding data link in response to the means for claiming the active control of the distributed IP gateway and based on determining the shared MAC address is assigned to a layer 2 virtual large area network (VLAN) group that is configured for multichannel link layer communications, the instruction enabling the connected network switching device to operate concurrently with the apparatus as part of the distributed IP gateway based on concurrent use of the shared MAC address and the shared IP address by the apparatus and the connected network switching device.

15. An apparatus comprising: a distributed gateway protocol circuit configured for: establishing a distributed IP gateway with a connected network switching device according to a prescribed protocol, the distributed IP gateway having a shared Media Access Control (MAC) address and a shared Internet Protocol (IP) address that is configured to enable network devices connected to the apparatus to reach the distributed IP gateway in a network, the distributed gateway protocol circuit configured for selectively claiming active control of the distributed IP gateway according to a prescribed protocol, the distributed IP gateway comprising at least two network switching devices operating concurrently with each other, the concurrent operation based on enabling a combined use of first hop redundancy protocols (FHRP) and multiple data link channels in the at least two network switching devices, and claiming active control over the distributed IP gateway; one or more network interface circuits having a plurality of network switch port circuits, each network switch port circuit configured for establishing a corresponding data link with one of the connected network devices or a connected network switching device; and a layer 2 forwarding circuit configured for receiving an instruction from the connected network switching device via the corresponding data link, the instruction specifying the shared MAC address to be used for reaching the distributed IP gateway based on the connected network switching device having claimed the active control of the distributed IP gateway and based on determining the shared MAC address is assigned to a layer 2 virtual large area network (VLAN) group that is configured for multichannel link layer communications, the instruction enabling the apparatus to operate concurrently with the connected network switching device as part of the distributed IP gateway based on concurrent use of the shared MAC address and the shared IP address by the apparatus and the connected network switching device.

16. The apparatus of claim 15 , wherein the layer 2 forwarding circuit is configured for forwarding a received packet to a prescribed IP gateway in response to the received packet specifying the shared MAC address and based on the layer 2 forwarding circuit detecting the apparatus operating in a standby state relative to the distributed IP gateway.

17. The apparatus of claim 16 , wherein the layer 2 forwarding circuit is configured for forwarding the received packet to the connected network switching device in response to determined unavailability of the apparatus reaching the prescribed IP gateway.

18. The method of claim 1 , wherein claiming active control over the distributed IP gateway occurs before assigning the shared MAC address to the shared IP address.

19. The method of claim 1 , wherein claiming active control over the distributed IP gateway occurs concurrently with assigning the shared MAC address to the shared IP address.

20. The method of claim 1 , wherein claiming active control over the distributed IP gateway occurs subsequent to assigning the shared MAC address to the shared IP address.

21. The method of claim 1 , wherein the enabling of the combined use of the FHRP and the multiple data link channels is achieved by the first network switching device sending an instruction via a peer data link to the second network switching device specifying the shared MAC address and configuring a multichannel link layer communication by assigning the shared MAC address to the layer 2 VLAN group.

22. The method of claim 1 , wherein the combined use of the FHRP and the multiple data link channels is characterized by the second network switching device configured to perform layer 3 forwarding and receiving of data packets while in a standby state or a listen state.

23. The method of claim 1 , wherein the FHRP comprises one of: Hot Standby Router Protocol (HSRP), Virtual Router Redundancy Protocol (VRRRP), and Gateway Load-Balancing Protocol (GLBP).